Narrative:

We were delayed on aircraft X from ZZZ to ZZZ1 after about 2.0 hours and 2 times back and forth to the gate we were told that we would be given a new aircraft due to maintenance. We deplaned and headed to a new gate. Upon flight attendant boarding I immediately noticed that we were now going to be traveling on aircraft Y. We were 3 flight attendants and 2 pilots. We had 3 deadheading flight attendants on board aircraft Y. I immediately mentioned to another flight attendant that I thought we were supposed to have 4 flight attendants now that we were on aircraft Y. She kinda shrugged it off. So I went to the purser and asked her. Her explanation was that because we still only had 113 passenger on board there was no problem. This was prior to passenger boarding! I got out my faom and saw that minimum crew on aircraft Y was 4. Unsatisfied with the explanation from my flying partners I went to the cockpit. The first officer said that he thought minimum crew was based on the number of seats not the number of occupants but he wasn't sure. Not the answer I would expect from someone who is second in command of a commercial jetliner. So when the captain came on board (he had stepped out for something); I voiced my concerns to him. Captain's answer was 'I don't know that's not my department' 'we are good to go...' I took this as captain authority/authorized seeing as I would hope that the man responsible for the entire aircraft; cargo; passenger; and crew would at the very least know what the FAA minimum is for his cabin crew. I did not make any more fuss. I might not make it through probation as we are all well aware that new hire flight attendants are terminated very frequently. I did not want to further delay a flight for fear of the consequences it might have on my career. The gate agent never mentioned that we might be under minimum crew and none of the 3 deadheaders said anything about it either. However a non-rev flight attendant about 1/2 through the flight said that he thought that we may be illegal but that was the first I heard anyone say anything about it.

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Original NASA ASRS Text

Title: 3 FLT ATTENDANTS DEPART ON ACFT CERTIFIED FOR 4.

Narrative: WE WERE DELAYED ON ACFT X FROM ZZZ TO ZZZ1 AFTER ABOUT 2.0 HRS AND 2 TIMES BACK AND FORTH TO THE GATE WE WERE TOLD THAT WE WOULD BE GIVEN A NEW ACFT DUE TO MAINT. WE DEPLANED AND HEADED TO A NEW GATE. UPON FLT ATTENDANT BOARDING I IMMEDIATELY NOTICED THAT WE WERE NOW GOING TO BE TRAVELING ON ACFT Y. WE WERE 3 FLT ATTENDANTS AND 2 PLTS. WE HAD 3 DEADHEADING FLT ATTENDANTS ON BOARD ACFT Y. I IMMEDIATELY MENTIONED TO ANOTHER FLT ATTENDANT THAT I THOUGHT WE WERE SUPPOSED TO HAVE 4 FLT ATTENDANTS NOW THAT WE WERE ON ACFT Y. SHE KINDA SHRUGGED IT OFF. SO I WENT TO THE PURSER AND ASKED HER. HER EXPLANATION WAS THAT BECAUSE WE STILL ONLY HAD 113 PAX ON BOARD THERE WAS NO PROB. THIS WAS PRIOR TO PAX BOARDING! I GOT OUT MY FAOM AND SAW THAT MINIMUM CREW ON ACFT Y WAS 4. UNSATISFIED WITH THE EXPLANATION FROM MY FLYING PARTNERS I WENT TO THE COCKPIT. THE FO SAID THAT HE THOUGHT MINIMUM CREW WAS BASED ON THE NUMBER OF SEATS NOT THE NUMBER OF OCCUPANTS BUT HE WASN'T SURE. NOT THE ANSWER I WOULD EXPECT FROM SOMEONE WHO IS SECOND IN COMMAND OF A COMMERCIAL JETLINER. SO WHEN THE CAPT CAME ON BOARD (HE HAD STEPPED OUT FOR SOMETHING); I VOICED MY CONCERNS TO HIM. CAPT'S ANSWER WAS 'I DON'T KNOW THAT'S NOT MY DEPT' 'WE ARE GOOD TO GO...' I TOOK THIS AS CAPT AUTH SEEING AS I WOULD HOPE THAT THE MAN RESPONSIBLE FOR THE ENTIRE ACFT; CARGO; PAX; AND CREW WOULD AT THE VERY LEAST KNOW WHAT THE FAA MINIMUM IS FOR HIS CABIN CREW. I DID NOT MAKE ANY MORE FUSS. I MIGHT NOT MAKE IT THROUGH PROBATION AS WE ARE ALL WELL AWARE THAT NEW HIRE FLT ATTENDANTS ARE TERMINATED VERY FREQUENTLY. I DID NOT WANT TO FURTHER DELAY A FLT FOR FEAR OF THE CONSEQUENCES IT MIGHT HAVE ON MY CAREER. THE GATE AGENT NEVER MENTIONED THAT WE MIGHT BE UNDER MINIMUM CREW AND NONE OF THE 3 DEADHEADERS SAID ANYTHING ABOUT IT EITHER. HOWEVER A NON-REV FLT ATTENDANT ABOUT 1/2 THROUGH THE FLT SAID THAT HE THOUGHT THAT WE MAY BE ILLEGAL BUT THAT WAS THE FIRST I HEARD ANYONE SAY ANYTHING ABOUT IT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.